Map showing depth to water table, September 1976, and area inundated by the June 1975 flood, Helena Valley, Lewis and Clark County, Montana

Depth to water table, September 1976, and area inundated by the June 1975 flood in the Helena valley, Montana, are mapped on two sheets, Helena and East Helena 7.5-minute quadrangles, at scale 1:48,000. Depth to water table was mapped using water-level measurements from existing shallow observation wells and selected domestic wells, and from field reconnaissance of topography. A hydrograph shows water-level fluctuation in two wells located in different parts of the valley. Area inundated by the June 1975 flood was mapped from aerial photos along Prickly Pear and Tenmile Creeks and by field reconnaissance along Silver Creek. (Woodard-USGS)